ADCMD_SETPREC

set the allocation precedence for audio channels

ADCMD_SETPREC is a command for multiple audio channels. For each selected channel (io_Unit), if the allocation key (ioa_AllocKey) is correct, ADCMD_SETPREC sets the allocation precedence to a new value (ln_Pri) and checks if there are allocation requests (ADCMD_ALLOCATE) waiting for the channel which now have higher precedence; otherwise, ADCMD_SETPREC returns an error (ADIOERR_NOALLOCATION). ADCMD_SETPREC is synchronous and only replies (mn_ReplyPort) if the quick flag (IOF_QUICK) is clear. Do not use ADCMD_SETPREC in interrupt code.

io_Message.mn_Node.ln_Pri

new allocation precedence (-128 thru 127)

io_Device

Pointer to device node, must be set by (or copied from I/O block set by) OpenDevice function

io_Unit

Bit map of channels to set precedence (bits 0 thru 3 correspond to channels 0 thru 3)

io_Command

Command number for ADCMD_SETPREC

io_Flags

Flags, must be cleared if not used: IOF_QUICK - (CLEAR) reply I/O request

ioa_AllocKey

Allocation key, must be set by (or copied from I/O block set by) OpenDevice function or ADCMD_ALLOCATE command

io_Unit

Bit map of channels that successfully set precedence (bits 0 thru 3 correspond to channels 0 thru 3)

io_Error

Error number: 0 - no error ADIOERR_NOALLOCATION - allocation key (ioa_AllocKey)

does not match key for channel